Speaking of Mer’s new secret sibling, Rhimes says the reveal that cardiothoracic surgery boss Maggie is the child of Richard and Ellis “will be influenced by what Meredith went through with Lexie,” her other (ill-fated) half-sis.

Rhimes reveals that this familial grenade is one she’s been wanting to pull the pin on “forever.” And then, about a month before the Season 10 finale, Rhimes says she told the writers, “‘Annnnd... we’re there,’ and they all [cheered]. So it’s pretty exciting.”